【单选题】下列羟基酸受热脱水,能生成α,β-不饱和酸的是( )。
【单选题】Part B Listening Comprehension Directions: In this part of the test there will be some short talks and conversations. After each one, you will be asked some questions. The talks, conversations and que...
B.
It's made by a professional organization covering nearly all parts of married life.
C.
It states in advance how many children they will have and where they'll live.
D.
It includes in advance the detailed rules to follow in nearly every part of the married life.
【简答题】请检索近十年发表在核心期刊上眼科针灸疗法的文献,并回答研究最多的前五名的机构有哪些?
【判断题】β-羟基丁酸受热发生分子内脱水生成α,β不饱和酸。
【单选题】下列哪种类型的羟基酸受热发生分子内脱水,生成不饱和酸?
【单选题】圆轴扭转时,同一圆周上的切应力大小( )。
【单选题】由于内扩散的影响,使得固体催化剂颗粒中反应物的浓度降低,内扩散对复合反应选择性的影响有以下的结论( )
D.
对于一级连串反应,内扩散的作用使得瞬时选择性降低
【单选题】圆轴扭转时,同一圆周上的切应力大小( )。